ImageMapper

Introduction

This class is not intended for general use. Please use the
similarly named class under Rendering/Core. This class is
a WebGL implementation of that generic renderable class in
Rendering Core. This class will automatically get instantiated
and rendered as needed by the OpenGLRenderWindow.

Source

index.js
import { mat4 } from 'gl-matrix';
import Constants from 'vtk.js/Sources/Rendering/Core/ImageMapper/Constants';
import macro from 'vtk.js/Sources/macro';
import vtkDataArray from 'vtk.js/Sources/Common/Core/DataArray';
import { VtkDataTypes } from 'vtk.js/Sources/Common/Core/DataArray/Constants';
import vtkHelper from 'vtk.js/Sources/Rendering/OpenGL/Helper';
import * as vtkMath from 'vtk.js/Sources/Common/Core/Math';
import vtkOpenGLTexture from 'vtk.js/Sources/Rendering/OpenGL/Texture';
import vtkShaderProgram from 'vtk.js/Sources/Rendering/OpenGL/ShaderProgram';
import vtkViewNode from 'vtk.js/Sources/Rendering/SceneGraph/ViewNode';
import { Representation } from 'vtk.js/Sources/Rendering/Core/Property/Constants';
import {
Wrap,
Filter,
} from 'vtk.js/Sources/Rendering/OpenGL/Texture/Constants';
import { InterpolationType } from 'vtk.js/Sources/Rendering/Core/ImageProperty/Constants';

import vtkPolyDataVS from 'vtk.js/Sources/Rendering/OpenGL/glsl/vtkPolyDataVS.glsl';
import vtkPolyDataFS from 'vtk.js/Sources/Rendering/OpenGL/glsl/vtkPolyDataFS.glsl';
import vtkReplacementShaderMapper from 'vtk.js/Sources/Rendering/OpenGL/ReplacementShaderMapper';

const { vtkErrorMacro } = macro;

const { SlicingMode } = Constants;

// ----------------------------------------------------------------------------
// helper methods
// ----------------------------------------------------------------------------

function computeFnToString(property, fn, numberOfComponents) {
let pwfun = fn.apply(property);
if (pwfun) {
const iComps = property.getIndependentComponents();
let pwfunToString = `${property.getMTime()}-${iComps}-0-${pwfun.getMTime()}`;
if (iComps) {
for (let c = 1; c < numberOfComponents; c++) {
pwfun = fn.apply(property, [c]);
if (pwfun) {
pwfunToString += `-${c}-${pwfun.getMTime()}`;
} else {
pwfunToString += `-${c}-none`;
}
}
}
return pwfunToString;
}
return '0';
}

// ----------------------------------------------------------------------------
// vtkOpenGLImageMapper methods
// ----------------------------------------------------------------------------

function vtkOpenGLImageMapper(publicAPI, model) {
// Set our className
model.classHierarchy.push('vtkOpenGLImageMapper');

publicAPI.buildPass = (prepass) => {
if (prepass) {
model.openGLImageSlice = publicAPI.getFirstAncestorOfType(
'vtkOpenGLImageSlice'
);
model.openGLRenderer = publicAPI.getFirstAncestorOfType(
'vtkOpenGLRenderer'
);
model.openGLRenderWindow = model.openGLRenderer.getParent();
model.context = model.openGLRenderWindow.getContext();
model.tris.setOpenGLRenderWindow(model.openGLRenderWindow);
model.openGLTexture.setOpenGLRenderWindow(model.openGLRenderWindow);
model.colorTexture.setOpenGLRenderWindow(model.openGLRenderWindow);
model.pwfTexture.setOpenGLRenderWindow(model.openGLRenderWindow);
const ren = model.openGLRenderer.getRenderable();
model.openGLCamera = model.openGLRenderer.getViewNodeFor(
ren.getActiveCamera()
);
// is slice set by the camera
if (model.renderable.getSliceAtFocalPoint()) {
model.renderable.setSliceFromCamera(ren.getActiveCamera());
}
}
};

publicAPI.translucentPass = (prepass) => {
if (prepass) {
publicAPI.render();
}
};

publicAPI.opaqueZBufferPass = (prepass) => {
if (prepass) {
model.haveSeenDepthRequest = true;
model.renderDepth = true;
publicAPI.render();
model.renderDepth = false;
}
};

publicAPI.opaquePass = (prepass) => {
if (prepass) {
publicAPI.render();
}
};

publicAPI.getCoincidentParameters = (ren, actor) => {
if (model.renderable.getResolveCoincidentTopology()) {
return model.renderable.getCoincidentTopologyPolygonOffsetParameters();
}
return null;
};

// Renders myself
publicAPI.render = () => {
const actor = model.openGLImageSlice.getRenderable();
const ren = model.openGLRenderer.getRenderable();
publicAPI.renderPiece(ren, actor);
};

publicAPI.buildShaders = (shaders, ren, actor) => {
publicAPI.getShaderTemplate(shaders, ren, actor);
publicAPI.replaceShaderValues(shaders, ren, actor);
};

publicAPI.getShaderTemplate = (shaders, ren, actor) => {
shaders.Vertex = vtkPolyDataVS;
shaders.Fragment = vtkPolyDataFS;
shaders.Geometry = '';
};

publicAPI.replaceShaderValues = (shaders, ren, actor) => {
let VSSource = shaders.Vertex;
let FSSource = shaders.Fragment;

VSSource = vtkShaderProgram.substitute(VSSource, '//VTK::Camera::Dec', [
'uniform mat4 MCPCMatrix;',
]).result;
VSSource = vtkShaderProgram.substitute(
VSSource,
'//VTK::PositionVC::Impl',
[' gl_Position = MCPCMatrix * vertexMC;']
).result;

VSSource = vtkShaderProgram.substitute(
VSSource,
'//VTK::TCoord::Impl',
'tcoordVCVSOutput = tcoordMC;'
).result;

VSSource = vtkShaderProgram.substitute(
VSSource,
'//VTK::TCoord::Dec',
'attribute vec2 tcoordMC; varying vec2 tcoordVCVSOutput;'
).result;

const tNumComp = model.openGLTexture.getComponents();
const iComps = actor.getProperty().getIndependentComponents();

let tcoordDec = [
'varying vec2 tcoordVCVSOutput;',
// color shift and scale
'uniform float cshift0;',
'uniform float cscale0;',
// pwf shift and scale
'uniform float pwfshift0;',
'uniform float pwfscale0;',
'uniform sampler2D texture1;',
'uniform sampler2D colorTexture1;',
'uniform sampler2D pwfTexture1;',
'uniform float opacity;',
];
if (iComps) {
for (let comp = 1; comp < tNumComp; comp++) {
tcoordDec = tcoordDec.concat([
// color shift and scale
`uniform float cshift${comp};`,
`uniform float cscale${comp};`,
// weighting shift and scale
`uniform float pwfshift${comp};`,
`uniform float pwfscale${comp};`,
]);
}
// the heights defined below are the locations
// for the up to four components of the tfuns
// the tfuns have a height of 2XnumComps pixels so the
// values are computed to hit the middle of the two rows
// for that component
switch (tNumComp) {
case 1:
tcoordDec = tcoordDec.concat([
'uniform float mix0;',
'#define height0 0.5',
]);
break;
case 2:
tcoordDec = tcoordDec.concat([
'uniform float mix0;',
'uniform float mix1;',
'#define height0 0.25',
'#define height1 0.75',
]);
break;
case 3:
tcoordDec = tcoordDec.concat([
'uniform float mix0;',
'uniform float mix1;',
'uniform float mix2;',
'#define height0 0.17',
'#define height1 0.5',
'#define height2 0.83',
]);
break;
case 4:
tcoordDec = tcoordDec.concat([
'uniform float mix0;',
'uniform float mix1;',
'uniform float mix2;',
'uniform float mix3;',
'#define height0 0.125',
'#define height1 0.375',
'#define height2 0.625',
'#define height3 0.875',
]);
break;
default:
vtkErrorMacro('Unsupported number of independent coordinates.');
}
}
FSSource = vtkShaderProgram.substitute(
FSSource,
'//VTK::TCoord::Dec',
tcoordDec
).result;

if (iComps) {
const rgba = ['r', 'g', 'b', 'a'];
let tcoordImpl = ['vec4 tvalue = texture2D(texture1, tcoordVCVSOutput);'];
for (let comp = 0; comp < tNumComp; comp++) {
tcoordImpl = tcoordImpl.concat([
`vec3 tcolor${comp} = mix${comp} * texture2D(colorTexture1, vec2(tvalue.${
rgba[comp]
} * cscale${comp} + cshift${comp}, height${comp})).rgb;`,
`float compWeight${comp} = mix${comp} * texture2D(pwfTexture1, vec2(tvalue.${
rgba[comp]
} * pwfscale${comp} + pwfshift${comp}, height${comp})).r;`,
]);
}
switch (tNumComp) {
case 1:
tcoordImpl = tcoordImpl.concat([
'gl_FragData[0] = vec4(tcolor0.rgb, opacity);',
]);
break;
case 2:
tcoordImpl = tcoordImpl.concat([
'float weightSum = compWeight0 + compWeight1;',
'gl_FragData[0] = vec4(vec3((tcolor0.rgb * (compWeight0 / weightSum)) + (tcolor1.rgb * (compWeight1 / weightSum))), opacity);',
]);
break;
case 3:
tcoordImpl = tcoordImpl.concat([
'float weightSum = compWeight0 + compWeight1 + compWeight2;',
'gl_FragData[0] = vec4(vec3((tcolor0.rgb * (compWeight0 / weightSum)) + (tcolor1.rgb * (compWeight1 / weightSum)) + (tcolor2.rgb * (compWeight2 / weightSum))), opacity);',
]);
break;
case 4:
tcoordImpl = tcoordImpl.concat([
'float weightSum = compWeight0 + compWeight1 + compWeight2 + compWeight3;',
'gl_FragData[0] = vec4(vec3((tcolor0.rgb * (compWeight0 / weightSum)) + (tcolor1.rgb * (compWeight1 / weightSum)) + (tcolor2.rgb * (compWeight2 / weightSum)) + (tcolor3.rgb * (compWeight3 / weightSum))), opacity);',
]);
break;
default:
vtkErrorMacro('Unsupported number of independent coordinates.');
}
FSSource = vtkShaderProgram.substitute(
FSSource,
'//VTK::TCoord::Impl',
tcoordImpl
).result;
} else {
// dependent components
switch (tNumComp) {
case 1:
FSSource = vtkShaderProgram.substitute(
FSSource,
'//VTK::TCoord::Impl',
[
'float intensity = texture2D(texture1, tcoordVCVSOutput).r;',
'vec3 tcolor = texture2D(colorTexture1, vec2(intensity * cscale0 + cshift0, 0.5)).rgb;',
'float scalarOpacity = texture2D(pwfTexture1, vec2(intensity * pwfscale0 + pwfshift0, 0.5)).r;',
'gl_FragData[0] = vec4(tcolor, scalarOpacity * opacity);',
]
).result;
break;
case 2:
FSSource = vtkShaderProgram.substitute(
FSSource,
'//VTK::TCoord::Impl',
[
'vec4 tcolor = texture2D(texture1, tcoordVCVSOutput);',
'float intensity = tcolor.r*cscale0 + cshift0;',
'gl_FragData[0] = vec4(texture2D(colorTexture1, vec2(intensity, 0.5)).rgb, pwfscale0*tcolor.g + pwfshift0);',
]
).result;
break;
default:
FSSource = vtkShaderProgram.substitute(
FSSource,
'//VTK::TCoord::Impl',
[
'vec4 tcolor = cscale0*texture2D(texture1, tcoordVCVSOutput.st) + cshift0;',
'gl_FragData[0] = vec4(texture2D(colorTexture1, vec2(tcolor.r,0.5)).r,',
' texture2D(colorTexture1, vec2(tcolor.g,0.5)).r,',
' texture2D(colorTexture1, vec2(tcolor.b,0.5)).r, tcolor.a);',
]
).result;
}
}

if (model.haveSeenDepthRequest) {
FSSource = vtkShaderProgram.substitute(
FSSource,
'//VTK::ZBuffer::Dec',
'uniform int depthRequest;'
).result;
FSSource = vtkShaderProgram.substitute(FSSource, '//VTK::ZBuffer::Impl', [
'if (depthRequest == 1) {',
'float iz = floor(gl_FragCoord.z*65535.0 + 0.1);',
'float rf = floor(iz/256.0)/255.0;',
'float gf = mod(iz,256.0)/255.0;',
'gl_FragData[0] = vec4(rf, gf, 0.0, 1.0); }',
]).result;
}

shaders.Vertex = VSSource;
shaders.Fragment = FSSource;

publicAPI.replaceShaderCoincidentOffset(shaders, ren, actor);
};

publicAPI.getNeedToRebuildShaders = (cellBO, ren, actor) => {
// has something changed that would require us to recreate the shader?
// candidates are
// property modified (representation interpolation and lighting)
// input modified
// light complexity changed

const tNumComp = model.openGLTexture.getComponents();
const iComp = actor.getProperty().getIndependentComponents();

if (
model.lastHaveSeenDepthRequest !== model.haveSeenDepthRequest ||
cellBO.getProgram() === 0 ||
model.lastTextureComponents !== tNumComp ||
model.lastIndependentComponents !== iComp
) {
model.lastHaveSeenDepthRequest = model.haveSeenDepthRequest;
model.lastTextureComponents = tNumComp;
model.lastIndependentComponents = iComp;
return true;
}

return false;
};

publicAPI.updateShaders = (cellBO, ren, actor) => {
model.lastBoundBO = cellBO;

// has something changed that would require us to recreate the shader?
if (publicAPI.getNeedToRebuildShaders(cellBO, ren, actor)) {
const shaders = { Vertex: null, Fragment: null, Geometry: null };

publicAPI.buildShaders(shaders, ren, actor);

// compile and bind the program if needed
const newShader = model.openGLRenderWindow
.getShaderCache()
.readyShaderProgramArray(
shaders.Vertex,
shaders.Fragment,
shaders.Geometry
);

// if the shader changed reinitialize the VAO
if (newShader !== cellBO.getProgram()) {
cellBO.setProgram(newShader);
// reset the VAO as the shader has changed
cellBO.getVAO().releaseGraphicsResources();
}

cellBO.getShaderSourceTime().modified();
} else {
model.openGLRenderWindow
.getShaderCache()
.readyShaderProgram(cellBO.getProgram());
}

cellBO.getVAO().bind();
publicAPI.setMapperShaderParameters(cellBO, ren, actor);
publicAPI.setCameraShaderParameters(cellBO, ren, actor);
publicAPI.setPropertyShaderParameters(cellBO, ren, actor);
};

publicAPI.setMapperShaderParameters = (cellBO, ren, actor) => {
// Now to update the VAO too, if necessary.

if (
cellBO.getCABO().getElementCount() &&
(model.VBOBuildTime > cellBO.getAttributeUpdateTime().getMTime() ||
cellBO.getShaderSourceTime().getMTime() >
cellBO.getAttributeUpdateTime().getMTime())
) {
if (cellBO.getProgram().isAttributeUsed('vertexMC')) {
if (
!cellBO
.getVAO()
.addAttributeArray(
cellBO.getProgram(),
cellBO.getCABO(),
'vertexMC',
cellBO.getCABO().getVertexOffset(),
cellBO.getCABO().getStride(),
model.context.FLOAT,
3,
model.context.FALSE
)
) {
vtkErrorMacro('Error setting vertexMC in shader VAO.');
}
}
if (
cellBO.getProgram().isAttributeUsed('tcoordMC') &&
cellBO.getCABO().getTCoordOffset()
) {
if (
!cellBO
.getVAO()
.addAttributeArray(
cellBO.getProgram(),
cellBO.getCABO(),
'tcoordMC',
cellBO.getCABO().getTCoordOffset(),
cellBO.getCABO().getStride(),
model.context.FLOAT,
cellBO.getCABO().getTCoordComponents(),
model.context.FALSE
)
) {
vtkErrorMacro('Error setting tcoordMC in shader VAO.');
}
}
cellBO.getAttributeUpdateTime().modified();
}

const texUnit = model.openGLTexture.getTextureUnit();
cellBO.getProgram().setUniformi('texture1', texUnit);

const numComp = model.openGLTexture.getComponents();
const iComps = actor.getProperty().getIndependentComponents();
if (iComps) {
for (let i = 0; i < numComp; i++) {
cellBO
.getProgram()
.setUniformf(`mix${i}`, actor.getProperty().getComponentWeight(i));
}
}

const oglShiftScale = model.openGLTexture.getShiftAndScale();

// three levels of shift scale combined into one
// for performance in the fragment shader
for (let i = 0; i < numComp; i++) {
let cw = actor.getProperty().getColorWindow();
let cl = actor.getProperty().getColorLevel();
const target = iComps ? i : 0;
const cfun = actor.getProperty().getRGBTransferFunction(target);
if (cfun) {
const cRange = cfun.getRange();
cw = cRange[1] - cRange[0];
cl = 0.5 * (cRange[1] + cRange[0]);
}

const scale = oglShiftScale.scale / cw;
const shift = (oglShiftScale.shift - cl) / cw + 0.5;
cellBO.getProgram().setUniformf(`cshift${i}`, shift);
cellBO.getProgram().setUniformf(`cscale${i}`, scale);
}

// pwf shift/scale
for (let i = 0; i < numComp; i++) {
let pwfScale = 1.0;
let pwfShift = 0.0;
const target = iComps ? i : 0;
const pwfun = actor.getProperty().getPiecewiseFunction(target);
if (pwfun) {
const pwfRange = pwfun.getRange();
const length = pwfRange[1] - pwfRange[0];
const mid = 0.5 * (pwfRange[0] + pwfRange[1]);
pwfScale = oglShiftScale.scale / length;
pwfShift = (oglShiftScale.shift - mid) / length + 0.5;
}
cellBO.getProgram().setUniformf(`pwfshift${i}`, pwfShift);
cellBO.getProgram().setUniformf(`pwfscale${i}`, pwfScale);
}

if (model.haveSeenDepthRequest) {
cellBO
.getProgram()
.setUniformi('depthRequest', model.renderDepth ? 1 : 0);
}

// handle coincident
if (cellBO.getProgram().isUniformUsed('coffset')) {
const cp = publicAPI.getCoincidentParameters(ren, actor);
cellBO.getProgram().setUniformf('coffset', cp.offset);
// cfactor isn't always used when coffset is.
if (cellBO.getProgram().isUniformUsed('cfactor')) {
cellBO.getProgram().setUniformf('cfactor', cp.factor);
}
}

const texColorUnit = model.colorTexture.getTextureUnit();
cellBO.getProgram().setUniformi('colorTexture1', texColorUnit);

const texOpacityUnit = model.pwfTexture.getTextureUnit();
cellBO.getProgram().setUniformi('pwfTexture1', texOpacityUnit);
};

publicAPI.setCameraShaderParameters = (cellBO, ren, actor) => {
const program = cellBO.getProgram();

const actMats = model.openGLImageSlice.getKeyMatrices();
const image = model.currentInput;
const i2wmat4 = image.getIndexToWorld();
mat4.multiply(model.imagemat, actMats.mcwc, i2wmat4);

const keyMats = model.openGLCamera.getKeyMatrices(ren);
mat4.multiply(model.imagemat, keyMats.wcpc, model.imagemat);

if (cellBO.getCABO().getCoordShiftAndScaleEnabled()) {
const inverseShiftScaleMat = cellBO
.getCABO()
.getInverseShiftAndScaleMatrix();
mat4.multiply(model.imagemat, model.imagemat, inverseShiftScaleMat);
}

program.setUniformMatrix('MCPCMatrix', model.imagemat);
};

publicAPI.setPropertyShaderParameters = (cellBO, ren, actor) => {
const program = cellBO.getProgram();

const ppty = actor.getProperty();

const opacity = ppty.getOpacity();
program.setUniformf('opacity', opacity);
};

publicAPI.renderPieceStart = (ren, actor) => {
// make sure the BOs are up to date
publicAPI.updateBufferObjects(ren, actor);

// Bind the OpenGL, this is shared between the different primitive/cell types.
model.lastBoundBO = null;
};

publicAPI.renderPieceDraw = (ren, actor) => {
const gl = model.context;

// activate the texture
model.openGLTexture.activate();
model.colorTexture.activate();
model.pwfTexture.activate();

// draw polygons
if (model.tris.getCABO().getElementCount()) {
// First we do the triangles, update the shader, set uniforms, etc.
publicAPI.updateShaders(model.tris, ren, actor);
gl.drawArrays(gl.TRIANGLES, 0, model.tris.getCABO().getElementCount());
model.tris.getVAO().release();
}

model.openGLTexture.deactivate();
model.colorTexture.deactivate();
model.pwfTexture.deactivate();
};

publicAPI.renderPieceFinish = (ren, actor) => {};

publicAPI.renderPiece = (ren, actor) => {
// Make sure that we have been properly initialized.
// if (ren.getRenderWindow().checkAbortStatus()) {
// return;
// }

publicAPI.invokeEvent({ type: 'StartEvent' });
model.renderable.update();
model.currentInput = model.renderable.getInputData();
publicAPI.invokeEvent({ type: 'EndEvent' });

if (!model.currentInput) {
vtkErrorMacro('No input!');
return;
}

publicAPI.renderPieceStart(ren, actor);
publicAPI.renderPieceDraw(ren, actor);
publicAPI.renderPieceFinish(ren, actor);
};

publicAPI.computeBounds = (ren, actor) => {
if (!publicAPI.getInput()) {
vtkMath.uninitializeBounds(model.bounds);
return;
}
model.bounds = publicAPI.getInput().getBounds();
};

publicAPI.updateBufferObjects = (ren, actor) => {
// Rebuild buffers if needed
if (publicAPI.getNeedToRebuildBufferObjects(ren, actor)) {
publicAPI.buildBufferObjects(ren, actor);
}
};

publicAPI.getNeedToRebuildBufferObjects = (ren, actor) => {
// first do a coarse check
if (
model.VBOBuildTime.getMTime() < publicAPI.getMTime() ||
model.VBOBuildTime.getMTime() < actor.getMTime() ||
model.VBOBuildTime.getMTime() < model.renderable.getMTime() ||
model.VBOBuildTime.getMTime() < actor.getProperty().getMTime() ||
model.VBOBuildTime.getMTime() < model.currentInput.getMTime()
) {
return true;
}
return false;
};

publicAPI.buildBufferObjects = (ren, actor) => {
const image = model.currentInput;

if (image === null) {
return;
}

const actorProperty = actor.getProperty();

// set interpolation on the texture based on property setting
const iType = actorProperty.getInterpolationType();
if (iType === InterpolationType.NEAREST) {
model.colorTexture.setMinificationFilter(Filter.NEAREST);
model.colorTexture.setMagnificationFilter(Filter.NEAREST);
model.pwfTexture.setMinificationFilter(Filter.NEAREST);
model.pwfTexture.setMagnificationFilter(Filter.NEAREST);
} else {
model.colorTexture.setMinificationFilter(Filter.LINEAR);
model.colorTexture.setMagnificationFilter(Filter.LINEAR);
model.pwfTexture.setMinificationFilter(Filter.LINEAR);
model.pwfTexture.setMagnificationFilter(Filter.LINEAR);
}

const numComp = image
.getPointData()
.getScalars()
.getNumberOfComponents();
const iComps = actorProperty.getIndependentComponents();
const numIComps = iComps ? numComp : 1;
const textureHeight = iComps ? 2 * numIComps : 1;

const cfunToString = computeFnToString(
actorProperty,
actorProperty.getRGBTransferFunction,
numIComps
);

if (model.colorTextureString !== cfunToString) {
const cWidth = 1024;
const cSize = cWidth * textureHeight * 3;
const cTable = new Uint8Array(cSize);
let cfun = actorProperty.getRGBTransferFunction();
if (cfun) {
const tmpTable = new Float32Array(cWidth * 3);

for (let c = 0; c < numIComps; c++) {
cfun = actorProperty.getRGBTransferFunction(c);
const cRange = cfun.getRange();
cfun.getTable(cRange[0], cRange[1], cWidth, tmpTable, 1);
if (iComps) {
for (let i = 0; i < cWidth * 3; i++) {
cTable[c * cWidth * 6 + i] = 255.0 * tmpTable[i];
cTable[c * cWidth * 6 + i + cWidth * 3] = 255.0 * tmpTable[i];
}
} else {
for (let i = 0; i < cWidth * 3; i++) {
cTable[c * cWidth * 6 + i] = 255.0 * tmpTable[i];
}
}
}
model.colorTexture.create2DFromRaw(
cWidth,
textureHeight,
3,
VtkDataTypes.UNSIGNED_CHAR,
cTable
);
} else {
for (let i = 0; i < cWidth * 3; ++i) {
cTable[i] = (255.0 * i) / ((cWidth - 1) * 3);
cTable[i + 1] = (255.0 * i) / ((cWidth - 1) * 3);
cTable[i + 2] = (255.0 * i) / ((cWidth - 1) * 3);
}
model.colorTexture.create2DFromRaw(
cWidth,
1,
3,
VtkDataTypes.UNSIGNED_CHAR,
cTable
);
}

model.colorTextureString = cfunToString;
}

// Build piecewise function buffer. This buffer is used either
// for component weighting or opacity, depending on whether we're
// rendering components independently or not.
const pwfunToString = computeFnToString(
actorProperty,
actorProperty.getPiecewiseFunction,
numIComps
);

if (model.pwfTextureString !== pwfunToString) {
const pwfWidth = 1024;
const pwfSize = pwfWidth * textureHeight;
const pwfTable = new Uint8Array(pwfSize);
let pwfun = actorProperty.getPiecewiseFunction();
if (pwfun) {
const pwfFloatTable = new Float32Array(pwfSize);
const tmpTable = new Float32Array(pwfWidth);

for (let c = 0; c < numIComps; ++c) {
pwfun = actorProperty.getPiecewiseFunction(c);
if (pwfun === null) {
// Piecewise constant max if no function supplied for this component
pwfFloatTable.fill(255.0);
} else {
const pwfRange = pwfun.getRange();
pwfun.getTable(pwfRange[0], pwfRange[1], pwfWidth, tmpTable, 1);
// adjust for sample distance etc
if (iComps) {
for (let i = 0; i < pwfWidth; i++) {
pwfFloatTable[c * pwfWidth * 2 + i] = 255.0 * tmpTable[i];
pwfFloatTable[c * pwfWidth * 2 + i + pwfWidth] =
255.0 * tmpTable[i];
}
} else {
for (let i = 0; i < pwfWidth; i++) {
pwfFloatTable[c * pwfWidth * 2 + i] = 255.0 * tmpTable[i];
}
}
}
}
model.pwfTexture.create2DFromRaw(
pwfWidth,
textureHeight,
1,
VtkDataTypes.FLOAT,
pwfFloatTable
);
} else {
// default is opaque
pwfTable.fill(255.0);
model.pwfTexture.create2DFromRaw(
pwfWidth,
1,
1,
VtkDataTypes.UNSIGNED_CHAR,
pwfTable
);
}

model.pwfTextureString = pwfunToString;
}

// Find what IJK axis and what direction to slice along
const { ijkMode } = model.renderable.getClosestIJKAxis();

// Find the IJK slice
let nSlice = model.renderable.getSlice();
if (ijkMode !== model.renderable.getSlicingMode()) {
// If not IJK slicing, get the IJK slice from the XYZ position/slice
nSlice = model.renderable.getSliceAtPosition(nSlice);
}

// Find sliceOffset
const ext = image.getExtent();
let sliceOffset;
if (ijkMode === SlicingMode.I) {
sliceOffset = nSlice - ext[0];
}
if (ijkMode === SlicingMode.J) {
sliceOffset = nSlice - ext[2];
}
if (ijkMode === SlicingMode.K || ijkMode === SlicingMode.NONE) {
sliceOffset = nSlice - ext[4];
}

// rebuild the VBO if the data has changed
const toString = `${nSlice}A${image.getMTime()}A${image
.getPointData()
.getScalars()
.getMTime()}B${publicAPI.getMTime()}C${model.renderable.getSlicingMode()}D${actor
.getProperty()
.getMTime()}`;
if (model.VBOBuildString !== toString) {
// Build the VBOs
const dims = image.getDimensions();
if (iType === InterpolationType.NEAREST) {
if (numComp === 4) {
model.openGLTexture.setGenerateMipmap(true);
model.openGLTexture.setMinificationFilter(Filter.NEAREST);
} else {
model.openGLTexture.setMinificationFilter(Filter.NEAREST);
}
model.openGLTexture.setMagnificationFilter(Filter.NEAREST);
} else {
if (numComp === 4) {
model.openGLTexture.setGenerateMipmap(true);
model.openGLTexture.setMinificationFilter(
Filter.LINEAR_MIPMAP_LINEAR
);
} else {
model.openGLTexture.setMinificationFilter(Filter.LINEAR);
}
model.openGLTexture.setMagnificationFilter(Filter.LINEAR);
}
model.openGLTexture.setWrapS(Wrap.CLAMP_TO_EDGE);
model.openGLTexture.setWrapT(Wrap.CLAMP_TO_EDGE);
const sliceSize = dims[0] * dims[1] * numComp;

const ptsArray = new Float32Array(12);
const tcoordArray = new Float32Array(8);
for (let i = 0; i < 4; i++) {
tcoordArray[i * 2] = i % 2 ? 1.0 : 0.0;
tcoordArray[i * 2 + 1] = i > 1 ? 1.0 : 0.0;
}

const basicScalars = image
.getPointData()
.getScalars()
.getData();
let scalars = null;
// Get right scalars according to slicing mode
if (ijkMode === SlicingMode.I) {
scalars = new basicScalars.constructor(dims[2] * dims[1] * numComp);
let id = 0;
for (let k = 0; k < dims[2]; k++) {
for (let j = 0; j < dims[1]; j++) {
const bsIdx =
(sliceOffset + j * dims[0] + k * dims[0] * dims[1]) * numComp;
id = (k * dims[1] + j) * numComp;
scalars.set(basicScalars.subarray(bsIdx, bsIdx + numComp), id);
}
}
dims[0] = dims[1];
dims[1] = dims[2];
ptsArray[0] = nSlice;
ptsArray[1] = ext[2];
ptsArray[2] = ext[4];
ptsArray[3] = nSlice;
ptsArray[4] = ext[3];
ptsArray[5] = ext[4];
ptsArray[6] = nSlice;
ptsArray[7] = ext[2];
ptsArray[8] = ext[5];
ptsArray[9] = nSlice;
ptsArray[10] = ext[3];
ptsArray[11] = ext[5];
} else if (ijkMode === SlicingMode.J) {
scalars = new basicScalars.constructor(dims[2] * dims[0] * numComp);
let id = 0;
for (let k = 0; k < dims[2]; k++) {
for (let i = 0; i < dims[0]; i++) {
const bsIdx =
(i + sliceOffset * dims[0] + k * dims[0] * dims[1]) * numComp;
id = (k * dims[0] + i) * numComp;
scalars.set(basicScalars.subarray(bsIdx, bsIdx + numComp), id);
}
}
dims[1] = dims[2];
ptsArray[0] = ext[0];
ptsArray[1] = nSlice;
ptsArray[2] = ext[4];
ptsArray[3] = ext[1];
ptsArray[4] = nSlice;
ptsArray[5] = ext[4];
ptsArray[6] = ext[0];
ptsArray[7] = nSlice;
ptsArray[8] = ext[5];
ptsArray[9] = ext[1];
ptsArray[10] = nSlice;
ptsArray[11] = ext[5];
} else if (ijkMode === SlicingMode.K || ijkMode === SlicingMode.NONE) {
scalars = basicScalars.subarray(
sliceOffset * sliceSize,
(sliceOffset + 1) * sliceSize
);
ptsArray[0] = ext[0];
ptsArray[1] = ext[2];
ptsArray[2] = nSlice;
ptsArray[3] = ext[1];
ptsArray[4] = ext[2];
ptsArray[5] = nSlice;
ptsArray[6] = ext[0];
ptsArray[7] = ext[3];
ptsArray[8] = nSlice;
ptsArray[9] = ext[1];
ptsArray[10] = ext[3];
ptsArray[11] = nSlice;
} else {
vtkErrorMacro('Reformat slicing not yet supported.');
}

model.openGLTexture.create2DFromRaw(
dims[0],
dims[1],
numComp,
image
.getPointData()
.getScalars()
.getDataType(),
scalars
);
model.openGLTexture.activate();
model.openGLTexture.sendParameters();
model.openGLTexture.deactivate();

const points = vtkDataArray.newInstance({
numberOfComponents: 3,
values: ptsArray,
});
points.setName('points');
const tcoords = vtkDataArray.newInstance({
numberOfComponents: 2,
values: tcoordArray,
});
tcoords.setName('tcoords');

const cellArray = new Uint16Array(8);
cellArray[0] = 3;
cellArray[1] = 0;
cellArray[2] = 1;
cellArray[3] = 3;
cellArray[4] = 3;
cellArray[5] = 0;
cellArray[6] = 3;
cellArray[7] = 2;
const cells = vtkDataArray.newInstance({
numberOfComponents: 1,
values: cellArray,
});

model.tris.getCABO().createVBO(cells, 'polys', Representation.SURFACE, {
points,
tcoords,
cellOffset: 0,
});
model.VBOBuildTime.modified();
model.VBOBuildString = toString;
}
};
}

// ----------------------------------------------------------------------------
// Object factory
// ----------------------------------------------------------------------------

const DEFAULT_VALUES = {
VBOBuildTime: 0,
VBOBuildString: null,
openGLTexture: null,
tris: null,
imagemat: null,
colorTexture: null,
pwfTexture: null,
lastHaveSeenDepthRequest: false,
haveSeenDepthRequest: false,
lastTextureComponents: 0,
};

// ----------------------------------------------------------------------------

export function extend(publicAPI, model, initialValues = {}) {
Object.assign(model, DEFAULT_VALUES, initialValues);

// Inheritance
vtkViewNode.extend(publicAPI, model, initialValues);
vtkReplacementShaderMapper.implementReplaceShaderCoincidentOffset(
publicAPI,
model,
initialValues
);

model.tris = vtkHelper.newInstance();
model.openGLTexture = vtkOpenGLTexture.newInstance();
model.colorTexture = vtkOpenGLTexture.newInstance();
model.pwfTexture = vtkOpenGLTexture.newInstance();

model.imagemat = mat4.create();

// Build VTK API
macro.setGet(publicAPI, model, []);

model.VBOBuildTime = {};
macro.obj(model.VBOBuildTime);

// Object methods
vtkOpenGLImageMapper(publicAPI, model);
}

// ----------------------------------------------------------------------------

export const newInstance = macro.newInstance(extend, 'vtkOpenGLImageMapper');

// ----------------------------------------------------------------------------

export default { newInstance, extend };